Compact discs, widely known as CDs, are usually packed into containers formed by two shells of plastic material, usually transparent. The shells are hinged together along a common edge.
While a first shell forms a bottom of the container and is shaped substantially like a box, a second shell has a shape complementary to the shape of the first shell, and forms a cover for the container.
Usually, closing devices for the (D containers are situated on a conveying line along which the containers are supplied with necessary contents e.g.: graphic leaflets, informative leaflets, sound medium, gadgets, etc.
Conventional devices for closing these shells are currently made of movable plates, which are suitably pivoted to a support structure so as to strike the cover shell thus making it close the related book-like container.
The most important disadvantages of these known devices derive from mechanical resistance required for the initial and final impacts imparted to the cover shell and the hinge around which the cover is rotated and overturned. Moreover, free rotation brings about possible unstability conditions.
The cover shell is moved in uncontrolled, random way, what provokes considerable mechanical stresses and "bounce effect" on the cover when it is struck by the movable plate as well as when it gets completely closed.
Moreover, closing steps, including a partial closing step and snap locking closing step, require considerably long time.